1. Field
The present invention relates, generally, to dental apparatus and methods. More particularly, the invention relates to dental drills, irrigators and air supplies. Most particularly, the invention relates to a system, apparatus and methods for providing drive, coolant, irrigation liquids, and mist air in a dental handpiece. The techniques of the invention can also be used in other fields such as medical and veterinary medical apparatus and methods.
2. Background Information
Dental hand pieces may provide means for drilling, drilling coolant, irrigation, mist air, air, and combinations thereof.
High speed drills and the like used in preparing teeth for filings and other work require that such equipment be kept at a temperature sufficient to not overheat while in the patient's mouth. High speed drills generate heat from friction as the drill contacts a tooth. Contact with a hot drill could burn delicate oral tissue. To minimize this problem, hand pieces typically utilize a coolant spray or mist, commonly water spray or mist, that encompasses the work area and is emitted from the distal end of the handpiece.
A problem which can occur in apparatus is backflow of saliva, blood, bacteria or other liquids from the mouth of the patient into the reservoir which houses the coolant. Apparatus such as those disclosed in U.S. Pat. Nos. 5,261,816; 5,261,816 and 4,973,247 may permit a backflow event which may potentially result in contamination of coolant and subsequent transfer of contaminated liquid mixture to patients. Disposable or sterilizable containers disclosed in the latter two patents may aid in avoiding such transfer of contaminated material.
Another potential problem that may occur is excess coolant flow after a handpiece is deactivated. This may cause a poor work field, inconvenience for the dentist, and discomfort for the patient.
Thus, to avoid this problem, mist air is desirable in certain dental procedures. However, mist air, or any air disturbance may embed debris in soft oral tissue. Therefore, coolant/mist should be carefully controlled.
Microbial conditions of compressed air often cannot be completely assured. Thus, when sterile procedures are recommended, mist air should be shut off completely and sterile irrigant (for example water) used in it's place. Some leakage of air may still occur through the turbine bearing on some handpieces. This can be minimized by not having an exhaust tube on the handpiece which improves free flow of air. Alternatively, a handpiece may be run on an inert gas such as Nitrogen.
Some microorganisms, including those found on dental handpieces maybe resistant to chemical disinfection. Therefore, autoclave (heat and pressure) disinfection or sterilization is desirable. A complete handpiece system, including the Handpiece, Water Line and Water/Water Container, that is amenable to autoclave disinfection and use in the sterile zone is desirable. It is particularly beneficial that the entire system be operable by the user with gloves on.
For these and other reasons, a need exists for the present invention.
All US patents and patent applications, and all other published documents mentioned anywhere in this application are hereby incorporated by reference in their entirety.